Temperature control system



43 v 50 25 Z9 26 if 38: aab 38 March 9,1948. HUNTER 2,437,468

TEMPERATURE CONTROL SYSTEM Filed Nov. 10, 1943 2 Sheets-Sheet l /9 o 1 T /5 I60 2 45 l l {ii I ,w l I P 96 g I 1P5:

h .m lmm fi fl .ATIUIENEY Patented Mar. 9, 1948 UNITED STATES PATENTtOFFlCE TEMPERATUREOONTBOL SYSTEM- Rutherford H. Hunter, Wooster, Ohio Application November 10, 1943, Serial No. 509,697

Claims. I

This invention relates to improvements in automatically operable thermostatic apparatus using the cubical expansion of a vaporized volatile fluid to produce a mechanical result. While intended to be used generally wherever it may be advantageously employed, the invention is particularly adapted for accurately controlling a source of heat to produce and maintain a desired temperature condition in an enclosed space.

The objects of the invention are to provide an improved pressure generator which includes a casing to be located within the space where a controlled temperature is desired, the casing closely confining a volatile liquid in which is mounted a bellows or hollow contractible element which is completely filled with a non-compressible liquid. The invention also aims to provide an improved valve and quick acting valve operating mechanism, the valve being interposable in a fuel line of a burner for heating said space and which includes a bellows or a suitable fluid operated means connected by a line to said pressure generator and to coordinate the operation of said elements with other elements herein disclosed to provide a highly efficient system of temperature control.

A further object is to provide a temperature controlled apparatus of economical construction which will be strong and durable and can be conveniently regulated to accurately maintain a desired temperature in a room or other enclosed space.

The above objects are accomplished and other obvious advantages attained by the novel construction, combination and arrangement of parts hereinafter described with reference to the accompanying drawing in which there is illustrated a preferred embodiment of the invention, it being understood that the same may be changed or modified to adapt it to particular conditions and that equivalent elements may be substituted erator 8 has a back plate l0, a cylindrical casing I I, having rearwardly projecting posts l2, l3 and 14 secured to said back plate by means of the screws l5 which are threaded in said posts. The casing II has an integrally formed top wall I8, completely closing the upper end thereof and a disc ll, having a central opening l8, which is which come within the scope of the appended claims.

In the drawings:

Figure 1 is a top plan view of a thermostatic pressure generator constructed in accordance with this invention.

Figure 2 is a side elevational view of same.

Figure 3 is a vertical cross-sectional view partly in front elevation, taken as indicated by the line 3-3 of Figure 2.

Figure 4 is a diagrammatic view showing in side elevation one method of operatively connecting the improved valves of this invention to a fuel line.

Figure 5 is a central vertical sectional view of the valves provided by this invention for controlling the flow of fuel to a burner or other heat producing means.

Proceeding now to a detailed description of the welded, brazed or otherwise impermeably secured in the lower end of said casing.

The numeral 20 denotes a bracket which is secured to the back plate ill to project forwardly beneath the lower end of the casing II, The bracket 20 has a vertically arranged tubular portion 21 which is coaxially arranged relative to the opening l8 and which is provided with a vertical bore in which is slidably mounted a shaft 22.

The bracket 20 includes a lug which curves downwardly and forwardly and terminates in a horizontal portion 24. The horizontal portion is provided with a threaded bore (not shown) in which is mounted from the lower end thereof a screw 25 to engage the lower end of the shaft 22. The shaft 22 projects upwardly into the cavity of the casing and is provided with an axial bore 26 which extends therein from the upper end thereof. An upper shaft 28 is slidably mounted in the bore 26 and projects upwardly beyond the shaft 22. The upper end portion of the shaft 23 is provided with an axial bore 29 in which is mounted the guide pin 30 which is secured to the upper wall iii of the casing ll whereby the shaft 28 is slidably movable therein. The shaft 28 terminates at the upper end thereof in an upwardly bulged disc 3| which has a horizontal marginal portion 32 disposed concentrically in the casing ll.

The shaft 22 is provided on the upper end thereof with an outwardly projecting annular shoulder 34 which forms the seat for the lower end of a coil spring 35 which is mounted on theshaft 28 for compression between the shoulder 34 and the disc 3|, the screw 25 being operable to regulate said compression.

A flat annular washer 4D is welded, brazed or otherwise secured to the lower wall H. The lower edge portion of the walls 38a and 38b are soldered, brazed or otherwise secured to the washer 40 to form a fluid-tight annular cavity 42 between said walls. The space 43 which surrounds the bellows 3 38 is also fluidtight and contains a volatile fluid prepared to vaporize at a certain selected temperature. A threaded bore 44 extends through the washer 48 and wall I1 and a suitable nipple 45 is threaded in said bore to communicate with the annular cavity 42. A tube 48 is connected to the nipple 45 and leads to the valve operating means hereinafter described.

In Figure there is shown a preferred form of the improved valve 1 which, as shown, has a tubular valve body 58 which is of conventional de-- sign with a partition 5| dividing the cavity of said body into an inlet cavity 52 and outlet cavity 53. A threaded inlet opening 55 leads to the cavity 52 and a threaded outlet opening 54 leads from the cavity 53.

The central portion 5Ia of the partition is horizontal and is provided with an opening 56 having an annular valve seat 51 disposed around said opening on the upwardly presented side thereof. The body 58 is provided on the lower side thereof with an enlarged opening 58 which communicates with the cavity 52. A downwardly projecting internal and external threaded nipple 68 surrounds said opening 58. A yoke ring 6| is threaded in said nipple and a yoke 62 depends from said ring and terminates in a horizontal portion 63. The horizontal portion 63 is provided with a centrally positioned threaded bore 64 and a pin 65 is threaded therein to project upwardly therefrom. A spring member 66 is secured to the bottom of the yoke 52 by the pin 55, and a nut 51 being threaded on said pin to hold the spring member 66 against the horizontal member 63. The end portions of the spring 66 project upwardly from the member 63 to form the spring arm 68 and 69. Each of the arms 68 and 58 are provided on the upper end thereof with a roller I8. The yoke is provided with screws II which may be operated against the spring arm 58 and 69 to regulate the tension thereof.

The numeral 12 denotes a valve stem which is positioned in said body and extends coaxially through the opening 56. The stem is reduced in diameter adjacent to said opening to provide a downwardly positioned shoulder 13 against which a valve disc I4 is secured by a nut'l5. The lower portion of the stem 12 is reduced in diameter to form a shoulder 16 against which is secured a disc 11 by a collar I8 which bears against the lower face thereof and is suitably secured thereto. An inverted truncated cone I8 is mounted on the lower end of the reduced lower end portion of the shaft I2. The cone I9 and the lower end portion of the shaft 12 is provided with a bore 12a in which is slidably received the pin 65. A cover 88 is threaded on the nipple 68 to completely enclose the mechanism above-described.

The body 58 is provided on the upper side thereof with an opening 82 which communicates with the cavity 53 and a flange 83 projects outwardly from said opening to provide a support for the bonnet hereinafter described. A washer 84 is positioned on said flange and a solid wall 85 is secured to the under side of said washer to completely close the opening 82. The wall 85 is provided with a centrally positioned opening 86 in which the shaft 12 is slidably received.

A disc 88 having a central opening 89 is secured to the upper end of the shaft 12 and a bellows 88 is coaxialiy positioned around the shaft 12 with its upper end soldered, brazed or otherwise secured to the disc 88.and its lower axial end likewise secured to the washer 84. The bellows 88 is preferably composed of copper but may be formed 4 of any suitable material and is provided with closely spaced, deep circumferential corrugations so as to be readily expansible or contractible as hereinafter described.

The shaft 12 is provided with an axial bore 92 which extends therein from the upper end there- 01 as shown in Figure 5 and a guide shaft 93 is slidably mounted in the bore 82. The shaft 93 has a disc 84 secured to the upper end thereof to form the upper wall of the snap bellows 95. The bellows 95 is similar to the bellows 88 and has its upper end soldered. brazed or otherwise secured to the disc 84 andits lower end likewise secured to the washer 88. The shaft 83 extends into the bore 82 to a point adjacent the end thereof so that a contraction of the bellows 95 will force the shaft 93 against the bottom of said bore and exert a downward force on the shaft 12.

Numeral 88 denotes a bonnet or casing open at the lower end and provided at said open end with a flange 81 which corresponds in outline to the flange 83 and is secured thereto by the bolts 98 to hold the washer 84 in place and form a fluidtight joint therebetween. The bonnet 98 thus encloses a fluid-tight space 99 which surrounds the circumferential and upper axial sides of the bellows 98 and 95. The bonnet 96 is provided with a threaded bore I88 in which is threaded connecting means IIII for securing the tube 46 thereto in communication with thespace 99.

The valve 8 is provided with a hollow valve body I having an internally threaded outlet nipple I86 and a similar inlet nipple I81. A partition I88 divides the cavity of the body I85 into an inlet chamber I88 and an outlet chamber H8. The central portion of the partition is horizontal and provided with an opening I I I. A valve seat II2 surrounds the opening III on the lower side of said partition I88. A valve stem I I4 is positioned in said body to extend coaxially through said opening. The body I05 is provided on the lower side thereof with an openin H5 and a cylindrical exteriorly and interiorly threaded nipple II5 surrounds said opening and projects downwardly therefrom. A closure II! is threaded in the nipple H6. The member II! has a thickened central portion provided with a bore I I8 in which is slidably mounted the reduced lower end II4a of the stem H4. The numeral H9 denotes a cover which is threaded on the nipple II6 to completely close the mechanism above-described.

The body I85 is provided on the upper side thereof with a. flat face I28 and with an enlarged opening I 2|. A tubular section I22 provided at the lower edge thereof with an outwardly projecting circumferentially extending flange I23 which is secured to the marginal portions of the face I28 by the bolts I24 and with the cavity of said tubular portion coinciding with the opening I2I. A flexible diaphragm I23 is positioned on the flat face I28 to completely close the opening I2I, the marginal portions of said diaphragm being tightly impinged between the flange I23 and the face I28.

The valve stem H4 is ofiset larger as at I21 to form a downwardly presented shoulder against which is positioned a disc I28. The central portion of the diaphragm is provided with an opening through which said valve stem II4 extends and the central portion of said diaphragm is held against the lower side of said disc I28 by the washer I38, a nut I3I being operated on said stem II4 to tightly impinge the central portion of the diaphragm between the disc I28 and with the shoulder indicated at I21. The diaphragm I25 is preferably formed of strong flexible impermeable material and the portion thereof extending between the disc I28 and the edge of'the opening i2I is in a free or unstrctched condition which will permit free movement of the stem H4. The reduced lower end portion I No of the stem I I4 extends upwardly to a plane below the valve seat II2 to form a downwardly presented shoulder against which the valve head I32 is securely held by the nut I33 which is threaded on said stem.

The disc I28 is provided with an upstanding circumferentially extending flange I28a to form a seat for the coil spring I38. The upper portion of the cavity of the section I22 is provided with a smooth cylindrical wall I38 and a washer I31 in said threaded portion I40. The wheel member I has an upwardly projecting hub I4Ia through which the shaft Il4 projects; a washer I42 having a hub I421) which projects upwardly therefrom is slidably mounted on the shaft II4 above the upper edge of the section I22. The hub M22: is enlarged at the upper end thereof to form an armature I 88. The washer MI is provided with a circumferentially extending flange I4Ia which forms a seat for the coil spring I45 which is mounted thereon. The upper end of the spring I45 bears against a disc I48 which is fixed to the upper end of the shaft H4. The

6 42 and with the space 88. A tube I82 is connected to the valve 1 to communicate with the space 82 or I08. In the drawings, the tube is shown as connected to the valve 1 to communicate with the inlet cavity 82, but it may be connected to said valves or to the line I80 in any suitable manner.

The tube I82 leads to the burner I8I and is provided in the free end thereof with suitable openings I83 to form a pilot light.

The numeral I84 denotes a thermopile which may be of any suitable construction, but is preferable of the compound type. The wires I54 and I55 are connected to the thermopile I84 and lead to the coils I5I and I82 to complete a circuit for the electricity generated by the thermopile I84 when the pilot light I83 is lit.

disc I48 is provided with 3. depending flange I41 electro-magnet M8 as illustrated includes the coils I5I and I52 and suitable core members I48a, but may be of any suitable construction. The magnet I48 is connected by the wires I54, I55 in an electric circuit hereinafter described.

It will be seen that the wheel I4I may be operated in the threaded barrel I40 so that the rim portion thereof will bear against the disc I31 and regulate the tension of the spring I35 or it may be operated to move the hub -I42b against the Washer I42 and regulate the tension of the spring The section I22 is offset smaller at the upper end thereof and a suitable hood I56 is threaded thereon to enclose the mechanism above-described. The hood I58 is provided in the upper wall thereof with a central opening I58, through which the upper end of the shaft I I4 projects.

In use, the pressure generator 8 is mounted in the room or space to be heated and the valves 1 and 8 are operatlvely interposed in the fuel line I80 leading to the burner I8I of a iumace or other apparatus for heating the space in which the The space 43 is filled or Partly filled with a volatile liquid and the space 42, the tube 48 and the space 88 with oil, alcohol or other noncom pressible liquid.

The projecting portion of the stem I I4 is pressed downwardly to open the valve I32 and the pilot light formed by the tube I82 is ignited. The heat generated by the pilot light generates suflicient electricity in th thermopile I82 and energizes the coils I5I and I52 causing the cores H811 to hold the armature I43 in the position shown in Figure 5. This compresses the spring lghand holds it in an inoperativepositionwhereby' the spring I35 will move the valve I32 to an open position.

As the heat generated by the burner I8I is conducted to the space in which the pressure generator 8 is positioned, it causes the fluid in the space 43 to volatilize and the vapor thereof to expand. The pressure of the expanding vapor exerts a force on the bellows 88 and compresses the bellows in accordance with the temperature of the room. This compression causes the liquid in the cavity 42 to be forced into the tube 48 and into the space 88 which compresses the bellows and 85 in accordance with the temperature of the volatile liquid in the space 43.

As the temperature of the room rises, the stem 12 is forced downwardly with the spring pressed roller 80 contacting with the conical surface of the member 18 to restrain the closing movement of the valve until the valve head 14 is close to the seat 51. As the valve head 14 nears a closed position, the conical member 18 is forced to a position where the rollers 80 snap over the upper edge of the said member, the releasing the restraining load of the spring arms 88 and 68, whereupon the compressed air in the snap bellows 85 will quickly complete the closing movement.

As the temperature of the room lowers, the volatile liquid in the space contracts and the spring 35 expands the bellows 38 thus drawing the'liquid from the space 88 to the space 43. As the rollers 10 are positioned over the upper edge of the conical member 18, a slight release of pressure will not open the valve, but when the pressure has been reduced to a certain point, the

compressed air in the snap bellows 85 will cause or gas to flow freely to and from the interior of end connected to the member IOI whereby the bore of the tube 48 communicates the bellows 80.

It will thus be seen that this invention provides simple inexpensive means for accurately regulatwlth the cavity 75 ing the operation of heating apparatus to heat and maintain the atmosphere a room or other space at a certain selected temperature.

The operation of the valve 8 may be initially regulated b operating the wheel I in the threaded portion I40.

When the valve 14 is closed, the pilot light I will heat the thermopile I64 and generate suflicient electricity to hold the spring I46 in a compressed or inoperative position. If, however, the supply of fuel is for any reason discontinued. the magnet formed by the coils l| and I52 will release the armature I43 and the spring I45 will raise the stem H4 and close the valve I32, thus preventing the escape of gasuntil the valve I32 is opened by manually depressing the stem H4 and igniting the pilot light I63.

While the valves 7 and 8 are described as two separate devices, they operate as a single unit to produce a desired, highly important result and that the pressure regulator 6 operates with the valves 8 and9 to produce this result.

Having thus illustrated a particular adaptation of my invention, what I claim as new and desire to secure by Letters Patent 1. In apparatus for regulating the operation of heating apparatus to produce and maintain a desired temperature in an enclosed space, an enclosed casing to be located in said space, a. hollow oontractible container mounted in said casing and having spaced concentric walls, a volatile fluid positioned in said casing around the container to exert an expansive force on said container for contracting it, a spring within the inner wall acting on said container to resist said expansive force and normally return it to an expanded condition, means to adjust the tension of said spring, a valve interposed in a fuel line leading to the burner of said heating apparatus, and means operated by fluid pressure for actuating said valve, a line leading from the pace between the concentric walls of said hollow contractible container to said valve operating means, said hollow container and line filled with a suitable fluid for communicating the expansive force of said volatile liquid to said valve operating means.

2. In apparatus for maintaining a. desired temperature in an enclosed space, an enclosed casing to be located in said space, a normally expanded contractible container positioned in said casing and having spaced concentric walls, a volatile fluid positioned in said casing around the container to exert an expansive force on said container for contracting it, a valve interposable in a fuel line leading to a burner for heating said space and means operated by fluid pressure for actuating said valve, said means including an enclosed hood, a bellows in said hood, a tube leading from the space between the concentric walls of said contractible container to said hood, said contractibie container, tube and hood filled with a non-compressible fluid whereby the expansive force of said 'volatile fluid will compress said bellows and actuate said valve.

3. In a thermostatically operated fluid pressure generator, a casing; a bellows having concentrically arranged spaced inner and outer walls and end walls enclosing an annular cavity, said inner and outer walls having circumferentially extending deeply folded contiguous corrugations, said bellows positioned in said casing with one axial end wall thereof impermeably secured to one wall of said casing; a disc secured over the free axial end of said bellows and closing the adjacent end of the central opening formed by said inner wall to form a fluid-tight space between the wall of the casing and said bellows; a thermal expansion fluid in said fluid-tight space; a non-compressible liquid in the cavity of said bellows and a line leading from said cavity to pressure operated means whereby the force of expansion of said thermal expansion fluid will be conducted by said fluid to said pressure operated means; and a spring positioned within the space enclosed by said inner wall to bear against said disc for resisting the expansive force of said thermal expansion fluid and normally return the bellows to an expanded condition and means to regulate the tension of said spring.

4. In a thermostatically operated fluid pressure generator a casing; a bellows having concentrically arranged spaced inner and outer walls and end walls enclosing an annular cavity, said inner and outer walls having circumferentially extending deeply folded contiguous corrugations, said bellows positioned in said casing with one axial end wall thereof impermeably secured to one wall of said casing; a member secured to the free axial end of said bellows and closing the adjacent end of the central opening formed by said inner wall and enclosing a fluidtight space between the wall of the casing and said bellows; a thermal expansion medium in said fluidtight space; a non-compressible liquid in the cavity of said bellows and a line leading from said cavity to pressure operated means whereby the force of expansion of said thermal expansion medium will be conducted by said fluid to said pressure operated means; and aspring positioned within the space enclosed by said inner wall to bear against said disc for resisting the expansive force of said thermal expansion medium and normally returnthe bellows to an expanded condition.

5. In apparatus for maintaining a desired temperature in an enclosed space, an enclosed casing located in said space, a normally expanded contractible container having'spaced concentric contraotible walls in said casing, said casing containing a volatile fluid adapted to contract said container, a valve interposed in a fuel line leading to a .burner for heating said enclosed space, means operated by fluid pressure for actuating said valve, said means including a hood enclosing a bellows, means operatively connecting said bellows to said valve, a snap bellows secured to said main bellows as an extension thereto, means providing a lost motion connection between said snap bellows and said valve operating means, and a tube leading from the space between the concentric walls of said contractible container to said hood, said contractible container, tube and hood being filled with non-compressible fluid..

RUTHERFORD H. HUNTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,300,717 Fulton Apr, 15, 1919 1,841,211 Ryden et'al. Jan. 12, 1932 2,053,974 Smith Sept. 8 1936 2,198,895 Wetzel Apr, 30, 1940 2,221,347 Giesler Nov. 12, 1940 2,264,677 Oxland Dec. 2, 1941 2,270,037 Corbin Jan. 13, 1942 2,312,479 Ray Mar. 2, 1943 2,318,767 Engholdt May 11, 1943 2,362,338 Anderson Nov. 7, 1944 

